Update the Configuration File for Db2 Region and Cross-Region Databases

Use these steps to create or update a configuration file to include entries to one or more region databases, and a cross-region databases.

You should only create or update a configuration file using the dbfhconfig command line utility.

Open an command prompt.
Set the MFDBFH_CONFIG environment variable to locate the configuration file to be created or updated:
```
set MFDBFH_CONFIG=<location-and-name-of-file>
```
If you do not set this variable, a file named MFDBFH.cfg is assumed to be located in the current directory.

Note: The MFDBFH_SCRIPT_DIR environment variable is also required to point to the stored procedures used to interact with a datastore; however, this variable is implicitly set already when using an command prompt.
Add a database server instance that you intend to connect to:
```
dbfhconfig -add -server:<server-name> -provider:db2
```
where <server-name> is the name of the database server instance. An entry of localhost:<port> is also valid, which defaults to your machine name. If you have already updated the configuration file with the Db2 datastores, this entry will already exist, and you will receive a message informing you of this; you can skip to the next step.

Now specify the required databases within the instance.
Repeat the following step for each required region database:
```
dbfhconfig -add -server:<server-name> -dsn:<dsn-name> [-db:<existing-db>] -type:region -name:<region-name> -feature:<options> [-user:<user-name>] [-password:<password>] [-connect:<connection-string>]
```
where <dsn-name> is either the ODBC data source for the region database, or if you are using a connection string (instead of an ODBC data source), it is a unique name within the Db2 configuration in which to reference the datastore; <existing-db> (which is optional) is the name of an existing database in which to store the datastore - if this option is omitted, a new database is created; <region-name> is the name of the enterprise server region; <opts> are the optimizations to be applied to I/O operations; <user-name> and <password> are valid credentials for the instance - you do not need to specify theses if you are using a connection string; and <connection-string> is the database connection string if you are establishing a database connection without the use of an ODBC data source - see Database Connection Strings for the database-specific syntax.
<opts> can be one or more of:
- all - all available region features enabled (default).
- none - no region features enabled.
- [+|-]reslocking - enables\disables database resource locking.
Now add a reference to a single cross-region database:
```
dbfhconfig -add -server:<server-name> -dsn:<dsn-name> -type:crossregion [-user:<user-name>] [-password:<password>] [-connect:<connection-string>]  
```
where <dsn-name> is either the ODBC data source for the cross-region database, or if you are using a connection string (instead of an ODBC data source), it is a unique name within the Db2 configuration in which to reference the datastore.

Example configuration file

The following is an example of a configuration file that contains a datastore, a region database, and a cross-region database, using direct connection syntax. As the login credentials are required to establish a connection to this database, the secrets vault has also been enabled: see Configure a Secrets Vault for the Micro Focus Database File Handler for more information.

<datastores usevault="true">
   <server name="localhost:50000" type="db2" access="odbc">
      <dsn name="DB2.VSAM" type="datastore" dsname="VSAM" optio="none +ooseq" dbname="MYMFFILS" connect="$$vault$$"/>
      <dsn name="DB2.SEQ" type="datastore" dsname="VSAM" optio="none +ooseq" bitism:"32" userid="db2admin" password="$$vault$$"/>
      <dsn name="DB2.ESDEMO" type="region.cas" region="ESDEMO" feature="all" dbname="MYMFFILS" connect="$$vault$$"/>
      <dsn name="DB2.CROSSREGION" type="crossregion.cas" dsname="$XREGN$" dbname="MYMFFILS" connect="$$vault$$"/>
   </server>
</datastores>

Next, you must create the region and cross-region databases using the dbfhadmin command line utility.